Effects of accelerated aging on thermal, mechanical, and shape memory properties of a cyanate-based shape memory polymer: II atomic oxygen

Abstract

As a new kind of smart material with shape changing and fixing abilities, the shape memory polymer (SMP), has become a research hotspot for space deployment structures in recent years. In fact, studying the space environmental adaptability of SMPs is an urgent research task, promoting their application in the aerospace field. In this study, a chemical crosslinked cyanate-based SMP (Tg~206°C) was exposed to atomic oxygen in a ground simulation system. The irradiation effects of atomic oxygen were investigated in terms of microscopic morphology, chemical structure, thermal stability, mechanical properties, loss factor and the storage modulus. After exposure to atomic oxygen, the cyanate-based SMP showed obvious surface erosion. When the irradiation dose reached 1022 atoms/cm2, the surface was entirely peeled off, and a new uneven surface emerged. However, the damage resulting from erosion was only on the surface and had little effect on the mechanical performance or shape memory behavior. The tensile strength and elastic modulus remained nearly constant at 66 MPa and 2000 MPa, respectively. Further, the effect of sample thickness and depth of delamination should be comprehensively considered in practical applications. The shape memory properties remain excellent after atomic oxygen irradiation, and the average shape fixity and shape recovery rates were 98.2% and 99.3%, respectively.